KOKORO
by yuzu-cha
Summary: There once was a scientist who had a goal that he wanted to achieve no matter what. She was his only hope. AU SasuSaku.
1. Side A

**___a/n: _**___Inspired by and based on Vocaloid video of the same title. Listened to the Utada Hikaru version while writing this._

* * *

**_KOKORO_**

_But something was missing, there was one thing he couldn't do, and that was the program called a "heart"  
__(Kokoro, Vocaloid Original Song)_

* * *

He stood back in anticipation as a familiar sound began to fill up the once silent room. It came first as a whirring sound, like every other piece of machinery that he's worked with, but it didn't take long for the sound to die off into a soft humming. He remained in the same spot and watched as a pair of viridian eyes stared back at him. Ones he thought he'd never live to see again.

"Do you know who I am?"

He seemed to have held his breath as he waited for her to answer. Like always, he was mesmerized—mesmerized by her eyes that were observing him. Something that's _she's_ always done then and now: observing him.

The whirring noise from earlier came back briefly.

"You are Doctor Uchiha."

It wasn't until he heard her voice and her words, when he was faced with _reality_. Upon being reminded of the truth, his onyx eyes grew cold. Any bit of emotion he had shown earlier (the anticipation, excitement and _longing_), completely gone. He was void of emotion, just like her voice. He focused his eyes on his clipboard—he couldn't look at her eyes.

"Are there any problems with the system?"

"Everything is functioning properly."

The man nodded somewhat stiffly as he checked off something from his clipboard, trying to get used to her voice. How he wished it was the same vibrant, cheerful voice that _she_ had. He shook his head, deciding to focus on his current task.

"Do you know your name?"

"Sakura."

* * *

"What do you think a heart is?"

That was a question that the Doctor decided to ask her one day. He usually does so every now and then, talk about things that were strange to her.

"If you are asking about the organ, a heart is a multi-chambered organ that helps pumps blood through the human body," she answered in her usual textbook-answer form, "In my case, although I have a similar organ in my body, it does not function in the same way since I—"

"Sakura, what do you think a heart is?"

She simply stared back at the man; for him to repeat a question meant that there was a much deeper answer that he wanted... one that she probably couldn't provide.

"If you would like me to run a search Doctor, I can do that."

There was a moment of silence before he sighed and went back to his work.

"It's okay. Leave it."

* * *

Today was the first time they have someone visiting the lab. She stared back at the guest who kept glaring at her since he first saw her.

"Sakura, please go get us some tea."

It wasn't long after she left the room to get tea for Doctor Uchiha and his blond haired guest when there were sounds of things crashing to the ground filling the facility followed by an yell from the visitor.

"YOU BASTARD!"

There came an unfamiliar sound of someone's fist punching another's face, but she recognized the sound since it was programmed into her.

"Damn it! How could you do this? How could you do this to **_her?!_**_"_

There was a long pause. Perhaps now was an appropriate time to bring in the tea.

"Idiot, what do **_you _**know?"

"That you've gone completely insane Bastard. You're only going to hurt yourself in the end."

The guest didn't leave too long after that, and on his way out, he stared at her. It was no longer a glare, but there was something with the way he looked at her that perplexed her. She wasn't able to decipher the meaning; she may have to ask to get an update on that next time.

That day, both cups of tea remained untouched, and no one has ever come to visit since.

* * *

He was always working on that**_ same _**program.

"Is that a new system update?"

He seemed to be contemplating on an answer. Sometimes he would have an answer for her questions right away, and other times he would always look contemplative (she was able to get that update she requested from the time when the visitor was here) as if searching for the right words, or just debating on whether he wanted to answer her or not.

"It's a new program for you, but right now your body can't handle it."

"If you are concerned about the memories, it's already been backed—"

"No!" It was the first time she saw him reacting like that. And it was also her first time flinching, a reaction that showed surprise.

"Doctor?" Her voice had snapped him out of his thoughts.

"Sorry. I wasn't in a good mood." She nodded, and there was silence between them before he spoke again.

"Sakura."

"Yes?"

"I don't ever want you touching this alright?"

He always spoke to her firmly. But this time, there was something about his tone. She couldn't recognize _what _it meant, she just knew it was different, but she decided not to inquire any further. As always, she nodded back at him.

"I understand."

* * *

_"I don't ever want you touching this alright?"_

Despite it being forbidden, she still found herself staring at the file.

It's been a hundred years since Doctor Uchiha _last _spoke to her.

He once told her that humans had limited life spans, and they were always looking for different ways to prolong their life. She was one the results of such desires. Had it been something that **_he _**desired for himself? He never answered her. Even if he did, Death had already caught up with him a hundred years ago.

There would be no one else to complete his research… no one's ever been here since the first visitor came. No one will know of this project that he's worked on, even before she woke for the first time. Someone has to complete his research. She was the only one.

"Command," her voice was clear as it echoed in the empty lab, "Download file: KOKORO."

* * *

Memories. _They were __**her**__ memories_.

_"I love you with all my heart!"_

She… **_felt _**it. There was something wrong with her chest cavity.

_"Sakura… thank you."_

Something inside of her… burning, filling, spreading, expanding—there was something awakening inside of her. Memories. Emotions. Feelings. Sakura placed her hand over where her "heart" was; although it wasn't pumping blood through her mechanical body, it was beating as a result of the program. She was able to **feel** joy and happiness, and at the same time she felt grief, pain, and anguish.

He warned her already, and he was right. Her body can't handle all these things and she was breaking. This wasn't something a simple memory back-up could fix. No wonder he had urged her with such desperation (yes, she knew now that it was desperation in his warning back then) not to touch the file.

Her tears just wouldn't stop. She shouldn't be capable of crying, yet there were tears that kept coming.

"Sasuke-kun…"

* * *

/_ It was an unending cycle… of tears and pain _/

"Wow! I can't believe there'd be a research facility in such good condition down here of all places. Whoever's it was, they've done a great job at hiding this. It must be several hundred years old! You think we'll find anyone in here?"

"Are you looking for a corpse?" Came a sarcastic reply from his partner, "Just shut up and get some light in this place Idiot."

"Tch. Bastard."

He had moved his hands along the wall, looking for a switch or anything. His companion had found it first, and gave him a warning before switching it on. Light flooded in his dark-colored eyes, and the first thing he saw upon adjusting to the brightness was **_pink_**_._

"Whoa! You've gotta watch out for what you say. I almost thought it was really a corpse for a second…"

Of course it couldn't have been a corpse. They knew this place was sealed shut, any corpse found in here would have been decayed beyond recognition. It had to be a robot or cyborg of some kind. They were forbidden, but that didn't stop people from creating them in secret.

The blond-haired man moved closer, but _he _didn't move a single step from his spot.

"Heh… well, it looks like they were pretty advanced even back then." The blond noted as he reached a hand out to touch the pink locks, and the skin of her forehead. He'd imagine that it was cool to the touch, but probably felt real at the same time.

"This must be the most advanced piece of work that still hasn't been destroyed. Sucks that the Council's full of superstitious and traditional old crones—forbidding advanced technology and such… imagine how much improvements it'd make on this messed up country! Hey—"

The words died from his mouth as he gaped, shocked at what he was seeing.

"Oi, Sasuke." He called out, dropping the usually preferred nickname, "Are you okay?"

"What are you talking about?"

Naruto stood up from his crouched position and faced his friend, a look of concern on his face.

"Are you **_crying_**?"

The dark-haired man frowned, slightly offended by that comment, "What the hell are you ta—"

_"Ne, Sasuke-kun?"_

And he felt it.

He brought his hand up to his face, the back of his hand touching his wet cheek. There were tears. His tears.

_"We'll be together forever right?"_

_"Hn."_

"Hey," There was hint of panic in his friend's voice, "Sasuke, did something—"

"Shut up Naruto." He almost barked, a hint of desperation in his voice. He willed himself to calm down, and refused to panic like his friend was doing so right now. His eyes were still on the pink-haired sleeping figure before them, "Let me think for a bit."

_"You know… a simple 'yes' would've been nice."_

_"Don't be annoying."_

_She huffed as she turned away from him. Seeing her response, his shoulders slacked a little as he sighed._

_"Sakura."_

_"What do you want?"_

_"I love you."_

_"E-eh?"_

* * *

"I wonder if she has a name. Not the model names, but you know… a name-name?"

_"Could you say that again? I didn't hear you clearly the first time."_

"Sakura."

"Huh?" The blond blinked before turning towards the sleeping doll, his eyes narrowed, trying to see if her name was written anywhere on her, "Is it the hair?"

"Her name, Sakura."

"You know, you'd be more popular with the ladies if you would get the stick out of your..."

He didn't complete his sentence. Something about his friend's expression, when looking at _her_, was just so perplexing. In all his years of knowing him since childhood, the blond has never seen him so full of… emotion. Not like this. Naruto turned back towards the doll, to the one whom Sasuke called Sakura.

"Hey… do you think we can ever fix her? You know, get her to move again or something. We'll probably have to do it in secret though so those old crones won't—"

_"Too late, maybe another time."_

"I'll do whatever it takes. I will fix her."

_"I love you too Sasuke-kun."_

_Were these his own memories, or that of a dream? That of a time far far away._

* * *

_**a/n:**_ Hello! So I know the plot might be confusing and there are a lot of empty spaces, and background stuff for this AU-story, but as I was trying to figure it out myself, I decided it was best left like this. And do watch the video for Kokoro if you haven't—and listen to the Utada Hikaru version (someone made the song using a custom voice bank for her voice) it's hauntingly beautiful and was what inspired me to write this._  
_

If I ever continue! I may write this from another POV (first part was Sasuke's, then Sakura's and then Sasuke again, so maybe attempt at Sakura, Sasuke and Naruto's for the same scenes). Thank you for reading!


	2. Side B

**KOKORO**

* * *

_I want to learn about the "heart" that person was building for me to the end of his life.  
(Kokoro, Vocaloid Original Song)_

* * *

_"Sasuke-kun, I'm dying."_

The first person she saw when she opened her eyes was a man with dark hair and dark eyes. She observed him quietly, noting his attire: a white lab coat over a slate gray dress shirt and black pants. He was also holding a clipboard with a blue ballpoint pen attached. He stared at her very intently, as if he were anticipating something.

"Do you know who I am?"

She already knew who he was upon seeing him, despite having never seeing or meeting him before. Even his voice, which she heard for the first time today, was most familiar to her. Everything was already programmed into her prior to her wakening.

"You are Doctor Uchiha."

There was a change in his expression and his intent gaze melted away as he turned to his clipboard.

"Are there any problems with the system?"

There was something slightly different in his tone this time as well, but she dismissed it as she ran a quick diagnosis before answering him.

"Everything is functioning properly."

Doctor Uchiha nodded as he continued marking his clipboard, marking down her answers, going through his checklist of things to make sure everything was running smoothly.

"Do you know your name?"

"Sakura."

She already knew who he was upon waking up, and she already knew who and what she was upon waking up. She was an artificial being and he was her creator. She also knew that in this large white room, its location hidden to society outside, there were only the two of them.

* * *

"Sakura, why do people want to live forever?"

This was the first of his series of complicated questions that he planned to ask her after three days of almost nonstop testing since she first woke. He knew that she would answer him based on the data he's given her, or by searching the network, but he still wanted to ask her. He just wanted to know if there was a chance that her answers would end up like _hers_.

"Most humans fear death because that simply means the end of their life," she answered. "They do not wish to end their lives so naturally, they want to live forever."

Well, her answer wasn't too bad for a first try. _She _would've given a much more passionate speech about the meaning of life, emotions, bonds, dreams, desires and whatnot. And _she _would have probably argued with him for hours over their opposing perspectives, only to end up not speaking to him in the hours that followed until they grew tired of ignoring each other.

Sakura wouldn't argue with him, but because she didn't spontaneously initiate conversations (unless on the rare chance when she had a question) like _she _did, there would still be hours and hours of silence between the two of them.

He knew that with the other questions he planned to ask her, there would be days in which he would be frustrated to no end, but he still wanted to see and hear for himself of how she perceives the world, even if it's through a program. If he were to catch even a glimpse of _her _through this, then perhaps his goal is not too out of sight.

"Is it something you wish for too doctor?"

"What is?"

"Living forever."

He was momentarily taken aback by her question, and when he didn't answer her back, she had dismissed the question.

* * *

"Doctor, your lip is bleeding."

He lifted his hand to wipe off the blood the side of his mouth. And then he simply stared at the red stain on the back of his hand. His blood ran red, and their visitor who had angrily stormed off earlier had red blood running through his veins too, but Sakura's didn't. It was just what she said the other day when he had asked her about what a heart was—she didn't have blood running through her veins.

_"Why don't you go see her? What's so important that you won't even go see her? She's dying!"_

His friend's (if the blond still considered him as such) outrage was not uncalled for. Yes, he knew his experiment was out of complete selfishness. What he did was not fair to _her_; it was not fair to Sakura. But was he wrong for wanting to do this? Could things have been better if he had gone about this differently? Should he have talked to his friend beforehand? Should he just give up—

"Doctor?" He heard her calling him. He could tell now that her voice, though not quite the same, still had that hint of familiar clarity to it. Hearing her voice this time, rather than deflating his mood (like it happened the first time), had chased away his doubts. Yes, he was selfish, and what he's doing may be unfair, but he did not regret his decision. He had but one goal, and he was going to achieve it by his means.

"Doctor," she repeated again, projecting her voice a bit, "would you like for me to treat your injury?"

"Sakura," he responded finally, "thank you."

He couldn't tell if the look on her face was due to confusion as to why he just thanked her, or perhaps it triggered something inside of her. There were many "memories" he hid within her current program that were locked away, inaccessible by her. They were made only to activate once he installs the current program he's working on. But there's no telling if anything else may trigger some of them to surface.

"I haven't done anything yet doctor."

No, perhaps, it was too good to be true. Nonetheless, she had encouraged him to keep working on the "heart".

* * *

"Sakura, do you know who I am?"

"Sasuke-kun…"

He felt his heart leap, hope blossoming in his chest when he heard her voice. Yes, this is exactly how he remembered her voice. Sakura, this _is_ Sakura.

"Sakura," he almost couldn't contain the emotions from his voice, "Sakura, I—"

His voice was caught in his throat when he saw her slump to the ground, shaking. He dropped to his knees before her, grabbing her by the shoulders, "Sakura! Sakura! What's wrong? Can you hear me?" He shook her gently, afraid he would harm her further if he used too much force.

He felt one of her hands around his forearm, gripping it tightly with a strength that _she_ didn't have. Whatever happened is making her lose control of how much strength she is distributing throughout her body.

"I... I can't. Sasuke-kun, it hurts," she lifted her other hand and rested it against her chest, where her "heart" was. Sasuke watched in shock as tears streamed from her face.

No, those couldn't be tears. His shock quickly morphed into horror when he caught the scent of her "tears" and he realized what was happening. She was breaking and he was the cause of it. Her body couldn't handle those memories that were surfacing upon the program activating; the memories that he placed inside of her and the program that he made for her.

_"Sasuke-kun, when I am gone. Will you miss me?"_

He brought her body closer to himself and wrapped his arms around her in an embrace, not caring about his arm that was being crushed further by her distress. It wasn't supposed to be like this. He didn't envision his experiment, his plan, to turn out this way. He was so close to losing her _again_ and it was would have been his fault. He couldn't stay still to see what will happen next.

"Voice activation," he said against her hair in a slightly cracked voice, "Terminate program."

He felt her body stiffen, and he could feel her body humming louder and louder, the whirring noise which he grew so accustomed to was returning. He hated the noise so much because it simply reminded him of the truth, yet it brought him relief knowing that she was still functioning. He felt her body relaxing, and only then did he allow himself to relax as well.

He slowly released her from his hold, and moved back slightly. He watched as she straight stared ahead of her, not registering anything into her vision as she processed his command. She was going to terminate the program, and revert to her previous state, to the Sakura who called him "Doctor".

The pain he felt in his heart was greater than the pain from his now broken arm. There was no way he was going to continue this any longer, not if it's going to destroy her.

* * *

"Sakura, I'll be going out for an errand."

He looked like he had something else to say, and he usually did on those rare occasions when he left the lab, so Sakura remained still, her eyes still locked with his as she waited for further instructions.

Instead, he took a few strides forward until he was standing right in front of her. His gaze was intense, it was familiar to her but he always had that gaze every now and then. What she hadn't anticipated was his next move, when he had raised his hand and rested it against her cheek.

"I left some instructions in a letter for you, but that will be accessible at a later time."

She nodded, still unsure of how to respond to his gesture.

"Doctor?"

"Hm?"

"Is there something else?"

"No," he said in an almost-whisper; his eyes still locked with hers, "I just wanted to take a good look at your eyes."

* * *

"Hey." He looked up from his spot upon hearing the voice and saw a familiar mop of blond hair on the other side of his cell.

"Finally decided to pay me a visit?" He joked lightly, "Or did you just accidentally find out while you were snooping around?"

"If you just handed her over like they'd asked, things wouldn't turn out this way."

"You know I won't tell them, and I know you won't tell them either."

"You're not being fair." The blond ran and hand through his hair in frustration. His other hand was still gripping the metal bars of the cell that his friend was locked in, "Even if I'm against it, there's no way I'm going to—"

"I know," he said, a barely-there smirk on his lips, "That's just how you are."

"Damn it." There was a small echo of metal bars being rattled. The blond was never good at containing his anger well.

"Naruto, when I'm gone, for your own safety and your family's, don't look for her, or take care of her in my place. She'll easily outlive the both of us, and all those people in the Council. She'll be safe where she is. I already left her a message."

"So you **_knew_** all along that this was what's going to happen? You knew that they were going to execute you? And you still came? You're such a cruel bastard."

"Did _she_ say the same about me?"

"You wish," he scoffed, "_her _language was way more colorful than mine, Sasuke."

_"Will I see you tomorrow again Sasuke-kun?"_

At the memory of their last encounter, the dark haired man leaned back against the wall covered his eyes with his arm, "So this is the end for me."

After his friend had left, all he could think about was her and her pink hair, even until his last breath.

* * *

"Come in," he answered when he heard the knock on his door. His good dark eye met a pair of similarly dark eyes. It was a shame seeing such lack of emotion in the younger man's eyes, a result of the kind of upbringing and hardships that he had to go through since childhood.

"Well?" The younger man barked impatiently, waiting for him to speak.

"There's been an emergency," he finally spoke, "The Council has decided to send you and Naruto on a top secret mission. You two are to head out in three hours. I already told Naruto the details."

He saw the raised brow, his silent question for more details of the mission.

"According to some old records that were found, one of the city's prisoners from a while back had a secret lab where he was tampering with a forbidden experiment. We just got a lead just a few hours ago from the recon team that they may have found his lab."

"Just how long ago was 'a while back'?"

"About three hundred years ago."

He watched, amused by the change of expression in the young man's face. Knowing that he wasn't too pleased about all this information that only made him dislike their city more and more.

"And you think this lab would still be intact for you Council crones to pilfer from?"

He smiled, "I may be old, but not that old or wise enough to be part of our esteemed Council." At this comment, the younger man scoffed, "Wise? How about scheming and manipulative?"

"Now now," he said, in a warning tone, "You know to watch your mouth around here. Anyway, the recon team picked up some kind of electromagnetic wave disturbances from underground. They suspect that there's something down there that's causing it and the Council's convinced that it's the lab that they've been searching for since their predecessors' time."

"Kakashi, what exactly are they looking for from this lab?"

"Well that's the thing, they don't know. All they know from the records is that someone worked on a forbidden project and even in the face of execution he didn't say a word. We don't know what's in it, but there have been some ideas."

"And if there's nothing?"

"It won't be the first time, but they'll be disappointed nonetheless."

"Well then. I hope there really isn't anything then."

There was a light chuckle that filled the room before Kakashi responded, "Sasuke, I'm sure you'd love to be the one to tell them that the lab that they've been searching for still remains a legend."

"They'll probably execute me for bringing them such bad news."

"Ah, so humor does find it's way to you sometimes. That makes me happy."

"Shut up."

* * *

"Wait, you're planning to **_hide_** her from the Council?" Naruto asked, the shock of whatever just happened earlier was still lingering in his system.

It was strange seeing his friend holding the sleeping girl—no—doll… machine so gently as if she were an actual human being. He held her with such tenderness that he's never seen before in all the years they've known each other. They've known each other since they were just toddlers. Sure, he has seen a side of him that was more gentle and fun, but those were from their childhood years, and he was never like _this_.

"If you're going to stop me, I'm going to fight you."

"I…" Naruto stopped, not quite sure of how to respond. His shoulder slumped, "Why are you doing this anyway? I'm sure that she's the very thing that the Council has been looking for all this time. It all makes sense now."

Sasuke looked down and that's when Naruto saw just how much change that she was _still_ putting him through. Gone were the hard lines, even his semi-permanent scowl was not visible. He almost looked like the Sasuke that he knew from when they were younger, prior to his family's untimely death.

He didn't know why he spoke again, but he responded even before Sasuke explained anything, "I'll help you this time."

_"This time?"_

Naruto was shocked by his own words, unsure of why he said it and so did his friend, but the former shrugged it off. He crouched down until he was eye level with Sasuke, who still looked a little confused, "Come on, if we're going to hide her we have to do it before the second team reaches us. I know just the place to go."

When the dark haired man didn't move, Naruto reached his hand out for Sasuke's shoulder, giving him a firm shake.

"Trust me."

"Thanks."

* * *

_"Naruto."_

_The blond turned around, looking at his friend who was on the other side of those wretched metal bars. It pained him that they were to part like this._

_"Thanks for seeing me one last time."_

* * *

_**a/n:**_Hello again! I know I said I wasn't going to continue... but I thought I'd give it a go since ideas started popping in my head. Anyways~again, I know there's a lot let for imagination. Once again, this fic was inspired by the Utada Hikaru version of the Vocaloid Original Song, Kokoro. I know the end of this chapter just opens up a can of worms and now it doesn't look all that complete anymore =/ but please just look at this as a Side B to the first chapter. I did attempt to write some snippets for what could possibly happen next, but that leads the story in a more SciFi-ish direction, which wasn't really what I intended... but we'll see.

Thanks for reading!


End file.
